The key to stopping mold growth, Flemmings said, is to cut off its life source –– moisture. “You can’t just lock off a basement in moist air and expect no mold,” he said. “You have to create some kind of air flow.”

The U.S. Environmental Protection Agency recommends using dehumidifiers or fans to dry out a wet area. If you use a fan, though, be sure that it’s pointed out of the house –– through a door or window. If not used properly, fans can blow mold spores throughout a home, causing a much bigger contamination problem, according to the EPA.

It is estimated that 60 percent of basements and crawl spaces, whether they have been flooded or not, have mold. “A lot of the places we’ve been, the mold existed way before Sandy,” Flemmings said. If you want to be certain that your home is safe from mold, have an air-quality test conducted.

The CDC recommends that household humidity levels range between 40 and 60 percent. Anything above that, and mold can grow. Humidity levels are measured with a hygrometer, available in home-supply stores or online for $40 to $80.

If humidity is too high, mold will return even after it is chemically treated, according to the EPA. That’s because it is impossible to remove all mold spores from a home, no matter how thorough a cleanup might be.

High Efficiency Particulate Air purifiers, also known as HEPA filters, which are available for $200 to $400, do an excellent job of clearing the air of particles down to .3 microns (roughly the size of mold spores), but even they cannot clean all mold –– it’s that pervasive. When buying a HEPA purifier, be sure to choose a model that cleans “99.97 percent” of particulate matter.